The present invention claims priority from Japanese Patent Application No.9-130203 filed May 21, 1997, which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a printing system for monitoring and controlling a printing operation of a printer, a setting thereof and a charging by an upper computer and, particularly, to a charging processing thereof
2. Description of Related Art
Japanese Patent Application Laid-open No. Hei 1-241447 discloses a technique for charging a cost on a user of a printer, in which the printer is connected through an input/output channel controller to a host computer and a charging of cost is performed on the side of the printer and the charging data on the side of the printer is transferred to the host computer through the input/output channel controller.
A printing system disclosed in the above mentioned Japanese Patent Application is shown in FIG. 1. In the printing system shown in FIG. 1, a host computer 5 exchanges data with an input/output interface 71 through an input/output channel 6 and an input/output channel controller 70 of a printer 7.
The printer 7 includes a central processing unit (CPU) 75 for generally controlling respective portions thereof, a read-only-memory (ROM) 72 for storing a process control program for the CPU 75, a random-access-memory (RAM) 73 for storing various data, flag information and results of operations, etc., of the CPU 75, a data page buffer (DB) 78 for storing the data output from the CPU 75 every page unit, a character pattern generator 77 for converting character codes in the data page buffer 78 into character pattern and supplying it to an output page buffer (PB) 79, an output device 80 for printing a dot information of the output page buffer 79, a disk 76 for storing a charging information and a console 74 for inputting a practical printing information or style and a content of data transferred to the host computer 5.
The input/output interface 71 includes an input/output buffer (IOB) for receiving and transmitting the transfer data and the RAM 73 is provided with an area for a start register (SR) and an end register (ER) for respectively storing a start day and an end day of a charging which are input from the console 74 as an instruction means and to be transferred to the host computer 5 and an area for a date counter (DC) used to count service days.
The charging information is accumulated every time when the output device 80 performs an output operation and stored in the disk 76. When a charging information read request is input from the host computer 5 to the printer 7, a block of data is read out from the disk 76, set in the input/output buffer of the input/output interface 71 and transferred from the input/output buffer to the host computer 5.
In a case where a charging is performed every producer of printing data or every section of printing data producers by the charging method of the above mentioned printing system, the printer itself must be provided with means for recognizing the printing data producers and/or the sections of printing data producers and means for storing the accumulated number of printing sheets (charging information) for every printing data producer or every section of printing data producers, resulting in an increase of cost of the printer.
That is, in the conventional printing system, only the start day and the end day are set and the charging information is obtained within the term defined by these days. Therefore, in order to obtain the charging information of every printing data producer or every section of printing data producers, it is necessary to set the start day and the end day for every printing data producer or every section of printing data producers and to calculate the charging information of every printing data producer or every section of printing data producers. Consequently, it is necessary to provide hardware or memory areas such as RAM's and/or disks separately in the printer, causing the cost of the printer to be increased.
Further, in, for example, a case where a printer is used commonly on a network, it is necessary to identify respective terminals accessing the printer and to calculate the charging information of the respective printers. Further, since a programming interface for totally handling the charging information is not provided, it is impossible to improve the operability of the printer in the network environment.